This invention relates to gas phase production of dialkyl carbonates from methanol, oxygen, and carbon monoxide.
Dimethyl carbonate is a valuable commercial product finding utility as a precursor to polycarbonates and isocyanates, as a solvent, and as a gasoline fuel additive.
Park and Lee report in Dioxygen Activation and Homogeneous Catalytic Oxidation, pages 631-640 (1991), that copper ion-exchanged Y zeolite was employed in a liquid phase reaction to produce dimethyl carbonate from methanol, carbon monoxide, and oxygen. While this catalyst brings about formation of dimethyl carbonate in a liquid phase reaction, this type of catalyst is not an effective catalyst when employed in a gas phase reaction. Since liquid phase reactions are oftentimes unattractive due to the corrosiveness of the reactants and products, it would be desirable to find an effective gas phase process for the production of dialkyl carbonates such as dimethyl carbonate.